fix ruler integration tests

[maxjeblick]

PR description

Fixes ruler integration test

Checklist

• Tests are working (make test)
• Code is formatted correctly (make style, on errors try fix with make format)
• Copyright header is included
• All commits are signed-off using git commit -s
• (new press) mypress_press.py is in the presses directory
• (new press) MyPress is in __init__.py
• (new press) README.md is updated with a 1 liner about the new press in the Available presses section
• (new press) New press is in the default_presses list in tests/default_presses.py
• (new press) A docstring is provided that follows the same structure as the existing ones